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AS level physics forces and motion question

A bullet is fired at an angle of 30° to the horizontal ground at a velocity of 200 ms-1.The bullet is in flight for a time t. Air resistance has a negligible effect on the motion of the bullet. What is the correct expression for the horizontal distance R travelled by the bullet?

A. R = 200 x cos30° x t

B. R = 200 x sin30° x t

C. R=((200 x cos30°)^2)/(2x9.81)

D. R=((200 x sin 30°)^2)/(2x 9.81)

The answer is A but I have no ideas on how to get it. Help me please!
A bullet is fired at an angle of 30° to the horizontal ground at a velocity of 200 ms-1.The bullet is in flight for a time t. Air resistance has a negligible effect on the motion of the bullet. What is the correct expression for the horizontal distance R travelled by the bullet?

A. R = 200 x cos30° x t

B. R = 200 x sin30° x t

C. R=((200 x cos30°)^2)/(2x9.81)

D. R=((200 x sin 30°)^2)/(2x 9.81)

The answer is A but I have no ideas on how to get it. Help me please!


Do you know how to find the distance travelled by a particle that is moving at constant velocity or constant speed in the same direction?

It is the same logic for this question.
Reply 2
Original post by Eimmanuel


Do you know how to find the distance travelled by a particle that is moving at constant velocity or constant speed in the same direction?

It is the same logic for this question.


No
No

This is gcse stuff. I recommend that you try to look back at your text.
Reply 4
S = ?
U = 200cos30
V= 200cos30
A = 0
T = t

U is the initial velocity. Now it’s at an angle and we want the horizontal component of the velocity so we do 200 COS 30 for horizontal. If you don’t know how i get this i would recommend going over projectile motion at an angle.

So now we’re looking for the horizontal distance traveled. We also know that the horizontal acceleration must be 0 because it has a uniform velocity (The velocity stays the same). Using this we can use

S = ut +1/2at^2

a is 0 so 1/2at^2 becomes 0 too so its
S = ut + 0
Plug in the values
S = 200cos30 x t

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